Here are the effects of caffeine on your body. Many of us can’t face the day without our morning cup of coffee. But caffeine does so much more than just keeping you awake..Caffeine the drug that gives coffee and cola its kick has a number of physiological effects. At the cellular level, caffeine blocks the action of a chemicaled phospho.sterase PDE ..Negative effects of caffeine on the body. Caffeine is a substance found in plants such as fruits and leaves. Among the caffeine can be found naturally in coffee, tea leaves, cocoa, and others. In the food and drink caffeine often found either naturally occurring or created by humans. This substance has few adverse effects to health, even storing deadly effects. But under certain conditions also beneficial to health.. Harmful Effects of Caffeine. The harmful effects of caffeine are sometimes harder to find information on than all of the reported positives. Here are a few of the stu.s that concluded that caffeine could be potentially dangerous to one’s health. Research Showing Harmful Effects of Caffeine. More than cups of coffee linked to early..